1. Field of the Invention
The present invention relates to an iris code generating device for generating an iris code and an iris identifying system for identifying individuals based on the iris code using the iris code generating device.
2. Description of the Related Art
An iris code is data in digital form for a pattern (hereinafter referred to as xe2x80x9ciris patternxe2x80x9d) of an iris in an eye. An iris code has remarkably different characteristics for each individual and can therefore be utilized in an iris identification system for identifying an individual.
This iris identifying system is utilized, for example, in a managed room access system for managing which people are allowed to enter or exit a room that identifies whether people entering or exiting a room are permitted to enter or exit the room.
It is anticipated that this iris identifying system will be utilized in the future in information communication systems for managing people""s access to networks such as the internet and for identifying whether or not a person accessing a network has the appropriate privileges to partake in services such as electronic settlements and electronic authentication.
The following is a description using the drawings of the configuration of a related iris identification system. In the following description, a person that is permitted to enter or leave a room or a person who has the appropriate privileges to partake in services is referred to as the xe2x80x9cauthorized personxe2x80x9d. A person subjected to identification as to whether or not this person is the authorized person is referred to as a xe2x80x9csubjectxe2x80x9d.
FIG. 10 is a view showing the configuration of a related iris identifying system. In FIG. 10, numeral 3 indicates an iris code generating device and numeral 8 indicates a host computer (hereinafter referred to as xe2x80x9cHOSTxe2x80x9d).
The iris code generating device 3 is comprised of a camera 4 for photographing an image 2 of an eye of a person 1 and a personal computer (hereinafter referred to as xe2x80x9cPCxe2x80x9d) 5. The PC 5 is comprised of an image capture board 6 for enlarging the image 2 of an eye photographed by the camera 4 and extracting an iris pattern from the image 2 of an eye and an iris code generator 7 for generating an iris code from an iris pattern.
The HOST 8 comprises a database 9 for storing data relating to people (for example, name, date of birth, etc.) and an authorized person matching section 10 for matching an iris code generated from the image 2 of an eye photographed by a camera 4 and an iris code stored on the database 9 and identifying whether or not the person 1 is the authorized person. The HOST 8 can also be modified to identify who the person is.
People with ill intentions are inclined to break into the iris identification system using some kind of illegal means. This kind of third party can consider, for example, stealing another person""s iris code and breaking into the system using this stolen code. A third party may also consider forging another persons iris code and try to break into the system using the forged iris code. A third party may also obtain a detailed image of an eye of another person and consider breaking into the system using the obtained image. Another possibility is that a third party may exchange structural components of the system (for example, the camera 4 or the image capture board 6, etc.) with an illegal device and attempt to break into the system by inputting false iris codes or false data into the system from the illegal device. The third party may consider connecting the illegal device to some point of the system so as to break into the system by inputting false iris codes or false data into the system from the illegal device. When a third party breaks into the system by these illegal means pretending to be another person the third party will appear to be the other person and a variety of crimes (including inappropriate deeds not yet defined in law as being illegal) can be carried out.
The object of the present invention is to provide an iris code generating device and an iris identifying system capable of detecting an intrusion into the system by illegal means and capable of preventing crimes from being committed.
In order to achieve this object, an iris code generating device of the present invention comprises a camera for photographing an image of an eye, an iris image processor for generating an iris code from an image of an eye photographed by the camera, a stimulation unit for causing a biogenic response in an eye of a subject and an authenticity determination processor for determining whether or not the image of an eye photographed by the camera is for a living thing in accordance with the biogenic response caused by the stimulation unit.
Further, the camera for photographing an image of an eye comprises a camera for photographing an image of an eye, an iris image processor for generating an iris code from an image of an eye photographed by the camera, a stimulation unit for causing a biogenic response in an eye of a subject and an authenticity determination processor for determining whether or not structural components of the system are authentic (for example, the camera and iris image processor, etc.) in accordance with the biogenic response caused by the stimulation unit.
The stimulation unit can comprise a light source for generating visible light and a light source for generating near infrared light. The stimulation unit can also comprise a plurality of light sources for generating near infrared light arranged around the periphery of a light source for generating visible light in such a manner that the light source for generating visible light is at the center of the light sources for generating near infrared light. In this configuration, the light source generating visible light is positioned opposite the center of the pupil of the subject and the plurality of light sources for generating near infrared light are positioned opposite the iris pattern at the periphery of the pupil. The intention of this configuration is that by adjusting the line of sight of the visible light that the subject can see, the visible light source will face the center of the pupil and the plurality of near infrared light sources will face the region at the periphery of the pupil. As a result of adopting this configuration for the stimulation section, the iris code generating device can photograph an image where the near infrared light and the iris pattern do not overlap and a superior iris code can therefore be generated.
The authenticity determination processor is configured so as to determine whether or not the image of an eye photographed by the camera 4 is for a living thing based on the position of light from the plurality of light sources for generating the infrared light depicted in the image of the eye. Alternatively, the authenticity determination processor determines whether or not the structural components of the system (for example, the camera and the iris image processor etc.) are authentic based on the position of light from the plurality of light sources generating infrared light depicted in the image of an eye.
The iris identifying system of the present invention has an iris code generating device and a database for storing iris codes of individuals and identifies individuals by matching an iris code generated by the iris code generating device and an iris code stored in the database.
The present invention can determine whether or not the image of an eye photographed by the camera is a living body. The present invention can also determine whether or not structural components of the system (for example, the camera and iris image processor etc.) are authentic. The present invention can therefore detect when the system is being broken into by illegal means and can prevent crimes from happening.